Currently, it has become more and more difficult for an optical network device constituted by separated optoelectronics devices to satisfy the requirement of an optical fiber communication network, which is undergoing rapid development. Photonic integrated chip (PIC) technology is a key technology for implementing an optical network with large capacity and low power consumption. In order to load external microwave signals on the photonic integrated chip effectively, an impedance matching microwave circuit with high efficiency, low reflection, and low loss is necessary for a transition heat sink.
Differently from the separated devices, an integrated device may have a dimension scaled down to micro-nano order due to its ultra-high integration, which puts forward stricter requirement on development and package of the device. A circuit design utilizing microwave waveguide generally employed in current separated device package is not suitable for array package. In cases where co-plane waveguide transmission line or micro-strip transmission line circuit typically used for single-way package is employed, a matching resistor is connected in parallel at the end of the transmission line. The matching resistor is difficult to manufacture due to dimension limitation of multi-way integrated device. If electrodes are elicited via gold wires, significant inductive effect may occur due to the dimension limitation of the device because the length of the gold wire may be too long or the diameter of the gold wire may be too small. As a result, there may introduce large number of parasite parameters and thus high-frequency performance of the whole array will be affected.
Moreover, the present disclosure may also address heat dissipation problem of the die array caused by the ultra-high integration.